Combustion-engine.



H. JUNKERS.

COMBUSTION ENGINE. APPLICATION riLnn 001 .7, 1907. 1,077,71 8. Patented Nov; 4, 1913.

witnesses? Inventor:

, HugoJunkers x. W. W W

.flttorney. V

nueo minimize, or man-cannula, ennrumr.

COMBUSTION-ENGINE. I

To all whom it may concern:

Be it known that I, HUGO JUNKERS, rofessor in the Royal Polytechnicum at 'ix- 'la-Chapelle, Germany, a subject of the King of, Prussia, residing at No. 64 Brabant- 'strasse, Aix-la-Chapelle, in the Kingdom of Prussia, Empire of Germany, have invented certain new and useful Improvements in Combustion-Engines; and I do hereby declare the following to be a full, clear, and

exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.-

My present invention relates to combustion-engines and in particular to improvements on the engine of the'two-stroke-cycle type described in my United States Patent No. 891,07 8 of June 16, 1 908, which engine is providedwith a separate chargingor compression-pump and with means for regulating and increasing the output ofthe-enme. t

The output of the two-cycle-engine described in my above-named patent is in creased by increasing the back-pressure in the cylinder during the charging-period by the aid of a throttling-device arranged in the exhaust-conduit. By means of this arrangement the working-cylinder is adapted to receive a larger char e than when working with atmospheric hack-pressure. Besides this arrangement of a throttling-device in the exhaust-conduit this engine is also provided with means for obtaining a greater filling of the working-cylinder.

The improvement described in the present application consists therein, that the throttling-deviceas embodied in the above named patent which is .o erated not periodically but more or less c osed in accordance with the duty demanded of the engine, is

replaced by a closingor throttling-device operated in accordance with the working periods of the engine, which closingor throttling-device, although operated by the governor or by hand, can be adjusted to suit. the duty of the engine. This throttling-device is to be governed by the engine in such a way, that it remains open atleast during a part of the exhaust-period, but is throttled or closed during the char 'ngperiod as soon as an increase of the ix ty,

igher than the normal, is required. ow much the throttling-device is to throttle-or speciflcatten'ot um" Tateat. Application med outta: 7,1901. semi 116.390,:80.

' PatentedNov.4,1913.

when this throttlingis to begin is determmed by a self-acting overnor or by an ad ustment executed by and. 7

Sometimes it is very advantageous to provide the engine with a uniformly acting throttling-device of the kind described in my United States Patent No. 891,078 of 'June 16, 1908, and also with a mechanically operated throttling-device of the kind disclosed in the present application. This throttling-device can be arranged between the engine and the exhaust-chamber, or beyond the latter, or again there may be a governed throttling-device arranged at both places simultaneously.

In accordance with the present invention, the main body of the exhaust gases is passed beyond the throttling device before the throttling begins. The compression consequently does not have to extend to this body of expanded and cooling gases, but is practically confined to the new charge. The regulation becomes more sensitive and efficient and the energy loss in charging is reduced. In order to efiect the charging most efficiently, a special arrangement of the charging or compression pump is hereinafter disclosed.

In the accompanying drawing :-Figure 1 is a longitudinal sectional view of a diagrammatically represented combustion-engine with a mechanically governed throttling-valve. Fig. 2 is a longitudinal sectional View of a diagrammatically represented combustion-engine with a mechanically operated throttling-valve and athrottling-valve operated by hand.

In the drawing all the parts of the engine not required for the illustration of my invention have been omitted for the sake of clearness and may be constructed in the usual manner.- In' both figures my improvement is shownin connection with a'doublepiston engine built in accordance with the United StatesPatent No. 508,833 of November 14, 1893, to Oechelhaeuser and Junkers, but might as well be shown in connection with any other two-'stroke-cycle engine, which acts either as an explosion-engine or as a combustion-engine for gaseous or liquid combustible's.

In the drawing 1 represents the workingcylinder of a two-stroke-cycle engine and 2 the front working-piston, whichin this instance controls the inlet-ports 3 and 4, whereas the rear working-piston 5 controls the exhaust-ports 6. As a matter of fact both' pistons might be interchanged. The gas is admitted into the workmg-cylmdenl through the inlet-ports 3 and the air through the inlet-ports 4, whereas the products of combustion pass through the ex.-.

haust-ports 6 into the exhaust-conduit 7, which is connected with the exhaust-chamber 8 and provided with the mechanlcally operated throttling-valve 9. Ad aCent to the latter the shaft 10 is journaled and rotated in the usual manner. Upon this shaft is seated a longitudinally movable sleeve 11 provided with a cam 12 which cooperates with the roller 13 to operate the valve 9. The governor 14 may be driven 1n any suitable manner and is operatlvely connected with said sleeve 11 by means of the bellcrank 15, so that the rotated cam 12 may be simultaneously moved longitudinally. The cam 12 is provided with a slanting surface arranged in such a manner that said valve 9 will be closed the earlier, the more the governor sinks when the engine. is over-.

loaded or in other words, that the free sectional area of the passage formed around said throttling-valve is reduced during the charging of the working-cylinder when the machine is overloaded, so that a throttling takes place during the charging-period, whereas the exhaust passage remains wide open during the time the products of combustion are exhausted therethrough.

In order to save labor, in connection with the pumping operations it is advisable that the chargingor compression-pump, or the auxiliary charging pump shown in my United States Patent No. 891,078 of June 16, 1908 be arranged in such a manner that during the charging-period a high pistonvelocity of the pump is maintained. --Fig. 1 shows one wayin which this can be accomplished. The pump 16 is here by way of example arranged at right angles to the working-cylinder l and operated by connecting its piston 17 to the same crank 18 which is driven by the piston 2, or by connecting it with another crank which lies in the same plane with the crank to which the connecting-rod 19 of the iston 2 is connected. On the down-stroke the piston 17 of this pum presses air through the conduit 20 into the working-cylinder 1 whereas on the lip-stroke saidpiston presses gas into the conduit 21, which must be sufficiently large to. act as a reservolr. The gas enters the working-cylinder 1 through the ports 3 when the piston 2 has almost reached the end of the out stroke. The valves of thepump are constructed as usual and therefore simply indicated whereas the suction-pipes are not shown at all. a

The arrangement shown in Fig. 2 diflers from "the one shown in Fig. 1 inasmuch-as n the outlet-opening 22 of the exhaust-chamber 23 a second throttling-valve 24 is arranged which may be adjusted by the aid of the, hand-lever 25 and closed the more, the more the duty of the engine is to be increased. a

In the accompanying drawing only two modifications of my invention are illustrated. The several parts of the engine might be arranged in a manner difiering from the arrangements shown in the drawing without departing from the nature of my invention. For instance, the mechanically -o erated throttling-valve can be arranged behind the exhaust-chamber, in which case the latter could be made smaller than for an engine such as that described in the United States Patent No. 891,078 of June 16, 1908. It is not necessary for the mechanically operated throttling-valve to close fluid-tight, so that any other closingor throttling-device, as for instance a common governed butter-flyvalve, may be employed, and it is not essential at all, by what means the valve is governed and influenced by the governor.

The operation of the engine is as follows: Referring particular y to the embodiment shown in the drawing, in which the throb tling device of the present invention is automatically controlled by the governor 14; when the engine is operating at normal duty, the exhaust ports 6 are opened by the piston near the end of the expansion stroke in the usual way. At that time the throttling valve 9 is wide open and permits the free exit of the main body of the products of combustion into the exhaust chamber 8, or to the atmosphere, if that chamber is not used. After the products of combustion have been expanded down to atmospheric pressure or thereabout, the valve actuating dev-ice affects the throttling valve to close it, thereby decreasing the area of the exhaust opening and consequently the outflow therethrough. The incoming charge, impelled by the charging pump of suitable capacity then forces out the remainder. of the products of combustion through the restricted. opening, and as soon as that has been accomplished the throttling valve may completely close at or about the instant of closure of the port 6 by the piston 5. This throttling of the exhaust permits the building up of pressure in the incoming charge without contaminating the new charge by the products of combustion, and the working cylinder is thus filled with an increased charge above atmospheric pressure. As load is thrown upon the engine and the consequent falling off in speed ensues, the controlling device affects the throttling valve to start the throttling action at an earlier time and thereby increases the final pressure of the charge. The cycle of the engine is not changed, but is merely earried out at a higher pressure and with more charge.

I claim 1. Means for increasing the charge in a two-stroke cycle internal combustion engine to increase the output thereof comprising a throttling valve controlling the cylinder exhaust outlet, and mechanism for actuating said valve to fully open theexhaust' outlet and permit the free exit of the products of combustion during the earlier portion of the exhaust period and to throttle the outlet and allow the building up of pressure and increase of the incoming charge during the later portion of the exhaust period; substantially as described. p

2. Means for increasing the charge in a twostroke cycle internal combustion engine to increase the output thereof comprising a throttling valve controlling the cylinder exhaust outlet, and mechanism for actuating said valve to fully open the exhaust outlet 25 and permit the free exit of the products of combustion during the earlier portion of the exhaust period and to throttle the outlet and allow the building up of pressure and increase of the incoming charge during the later portion of the exhaust period, said.

actuating mechanism being responsive to the load onthe engine to vary the throttling and thereby the cylinder charge according to the load; substantially as described.

3. Means forxincreasing the charge in a --two-stroke cycle internal combustion engine I to increase the output thereof comprising a throttling valve controlling the cylinder exhaust outlet, and mechanism for actuating said valve to fully open the exhaust outletand permit the free exitof the products of'cornbustion during the earlier portion of the exhaust period and to throttle the outlet and allow the building up of pressure and increase of the incoming charge'-du ridn g the later portion of the exhaust perio ,said actuating mechanism being responsive to the load on the engine and adapted to eflI'ect the throttling action earlier ally operated and for a longer time as the load increases;

substantialiy as described.

4. In-rzrtwo-stroke cycle internal combii tion engine, the combination with a wdi'king c linder having a charging pump in connection therewith and an exhaust outlet, of a throttling valve controlling the exhaust outlet, and mechanism for actuating said valve to fully open the exhaust outlet and permit the free exit of the products of combustion during the earlier portion of the exhaust period and to throttle the outlet and allow the building up of pressure and increase of the incoming charge during the later portion of the exhaust period, and mechanism for obtaining a high piston velocity of the charging pump during the period of introduction, of the charge into the working cylinder; substantially as described.

5. Means for increasing the charge in a two-stroke cycle internal combustion engine to increase thev output thereof comprising a throttling valve controlling the cylinder exhaust outlet, and mechanism for actuating said valve to full open the exhaust outlet and permit the rec exit of the products of combustion during the earlier portion of the-exhaust period and to throttle the outlet and allow the building up of pressure and increase of the'incoming charge during the later portion of the exhaust period, said actuating mechanism being responsive to the load on the engine to vary the throttling and thereby the cylinder charge according to the load, an exhaust chamber into which the exhaust outlet-discharges, and a manuthrottling device at the exit of said exhaust ing gases independently of the first mentioned throttling valve; substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HUGO J UNKERS.

Witnesses HENRY QUADFLIEG, Emsn KALBUSCH.

chamber to throttle the outgo- 

